BETADIST Function

The BETADIST (beta distribution) function is an effective statistical function used to model uncertainties in certain areas like risk management and project management (PERT). This function returns the cumulative beta probability density function.

Beta distribution is commonly used to study variation in the percentage of something across samples, like the fraction of children actively enrolled in evening swimming classes and the probability of casting votes.

The BETADIST function replaces the BETA.DIST function from Excel 2010.

Compatibility

This advanced Excel function is compatible with the following versions of MS-Excel −

Excel for Microsoft 365
Excel for Microsoft 365 for Mac
Excel for the web Excel 2021
Excel 2021 for Mac
Excel 2019
Excel 2019 for Mac
Excel 2016

Syntax

The syntax of BETADIST function is as follows −

BETADIST(x,alpha,beta,[A],[B])

Arguments

You can use the following arguments with the BETADIST function −

Argument	Description	Required / Optional
X	The value between A and B at which to evaluate the function.	Required
Alpha	A distribution parameter.	Required
Beta	A distribution parameter.	Required
A	It specifies the lower bound of the X argument.	Optional
B	It specifies the upper bound of the X argument.	Optional

Points to Remember

If any argument is other than a numeric value, BETADIST retrieves the #VALUE! error.
If the x parameter is less than A, x is greater than B, or the lower bound that is A is equal to the upper bound B, in that case, BETADIST retrieves the #NUM! error.
Either Alpha or Beta parameters are less than and equal to zero, BETADIST retrieves the #NUM! error.
If the x and b parameters have the same value, and the alpha and beta parameters are equal then the BETADIST returns 1.
If the Alpha equals Beta, then the distribution is considered as symmetrical.
Another variation of the beta distribution function is BETA.INV is just the opposite of it. The BETA.INV function retrieves the inverse of the Beta distribution function.

Examples of BETADIST Function

Practice the following examples to learn the use of the BETADIST function in Excel.

Example 1

Open a new Excel worksheet and write the text like x, Alpha, Beta, A, B, and Beta Distribution Value separately in range B2:B7. Enter its corresponding value in the C column as given below. You may write the formula = =BETADIST(C3,C4,C5,C6,C7) in the C8 cell and press the Enter tab to get its resulting value 0.27.

Example 2

If any argument is other than a numeric value, BETADIST retrieves the #VALUE! error.

Solution

You may enter the expression =BETADIST(7,"al",2,1,9) in the desired cell and press the Enter tab. In this expression, the Beta parameter value is non-numeric "al". Therefore, it will generate the #VALUE! error.

Example 3

If the x parameter is less than A, x is greater than B, or the lower bound that is A is equal to the upper bound B, in that case, BETADIST retrieves the #NUM! error.

Solution

You can enter the expression "=BETADIST(3, 1, 3, 9,6)" in the desired cell and press the "Enter" tab. Therefore, the resulting value is #NUM!. The reason behind the value of A(fourth) parameter 9 is greater than the x(first) parameter 3. The value of the A parameter must be smaller than the x parameter in the beta distribution function.

Example 4

Either Alpha or Beta parameters are less than and equal to zero, BETADIST retrieves the #NUM! error.

Solution

You can write the "=BETADIST(6,-8, 8, 2,6)" expression in the C4 cell and press the Enter.

As you may observe in the screenshot, the #NUM error occurred in this case.

Example 5

If the x and b parameters have the same value, and the alpha and beta parameters are equal then the BETADIST returns 1.

Solution

You may enter the expression "=BETADIST(11,8, 8, 2,11)" in the desired cell and press the Enter tab.

Therefore, the BETADIST function retrieves 1 in this case.

Save or share this article